bbb bbg bbo bbs bbt bbx bgb bgg bgo bgs bgt bgx bob bog boo bos bot box bsb bsg bso bss bst bsx btb btg bto bts btt btx bxb bxo bxx gbg gbo gbs gbt gbx ggb ggg ggo ggs ggt gob gog goo gos got gox gsb gsg gso gss gst gsx gtb gtg gto gts gtt gtx gxs gxt ob- obb obg obo obs obt obx ogg ogo ogs ogt ogx oo- oob oog ooo oos oot oox os- osb osg oso oss ost osx ot- otb otg oto ots ott ox- oxb oxo oxt oxx sbb sbg sbo sbs sbt sbx sgb sgg sgo sgs sgt sgx sob sog soo sos sot sox ss- ssb ssg sso sss sst ssx stb stg sto sts stt stx sxs sxt t-x tbb tbg tbo tbs tbt tgb tgg tgo tgs tgt to- tob tog too tos tot tox tsb tsg tso tss tst tsx ttb ttg tto tts ttt ttx txs txt xbx xog xoo xos xot xox xsb xss xst xts xtx xxo xxx